Clinical diagnostic analyzers are being developed with increasing levels of complexity and sophistication in order to fully automated the performance of chemical assays and immunoassays of biological fluid samples such as urine, blood serum, plasma, cerebrospinal liquids and the like, these fluid samples almost universally being contained in open or capped sample tubes. Generally, chemical reactions between an analyte in a patient's biological sample and reagents used during performing the assay result in generating various signals that can be measured by the analyzer. From these signals the concentration of the analyte in the sample may be calculated.
A wide variety of automated chemical analyzers are known in the art and are continually being improved to increase analytical menu and throughput, reduce turnaround time, and decrease requisite sample volumes. See for example, U.S. Pat. Nos. 6,103,193, and 6,027,691 and 5,482,861. Such improvements, while necessary in themselves, may be hampered if sufficient corresponding advances are not made in the areas of pre-analytical sample preparation and handling operations like sorting, batch preparation, centrifugation of sample tubes to separate sample constituents, cap removal to facilitate fluid access, and the like.
Analytical throughput may be increased by linking together analyzers of different types, each adapted to perform a certain menu of assays. Another is to link together two or more analyzers of the same type and to allocate incoming samples to whichever analyzer has the smallest backlog of samples to process. Alternately, incoming samples may be allocated between analyzers according to the number and availability of assay resources (reaction vessels, reagents, etc) required by the assay and duplicated on each analyzer.
U.S. Pat. No. 6,261,521 discloses a sample analysis system having a plurality of analyzers placed along a main conveyor line in combination with different types of reagent supply units, such that samples to be tested are assigned to an analyzer having the proper reagent.
U.S. Pat. No. 6,022,746 discloses a method for operating a multi-analyzer system by generating a list of tests to be performed by the system within a given reaction vessel. The list of tests is sorted according to the number of reaction vessels used in performing each test to be performed by the system in a given time period.
U.S. Pat. No. 6,019,945 discloses a transfer mechanism for transferring a sample container holder between a conveyor line and a sampling area formed in each of several analyzers, the transfer mechanism being connectable to each one of the plurality of analyzers. At least two analyzers units are different from one other in either the types of reagent supply means, the number of analysis items that can be analyzed, the number of tests that can be processed in a unit time, or the species of samples to be processed.
U.S. Pat. No. 5,087,423 discloses a plurality of analyzing modules, a plurality of analyzing routes and at least one bypass route bypassing at least one analyzing module are arranged. Each analyzing module is capable of analyzing samples with respect to one or more items, and samples successively supplied from the introduction sides of the modules are selectively delivered into each module.
Although these prior art systems have advanced sample handling and processing throughput, what has not been addressed is the increasing complexity associated with performing the proper quality control procedures within multi-analyzer automated clinical analyzer system. In particular, Laboratory Automation Systems typically have not dealt with the impact of Quality Control procedures on the analytical clinical analyzers they automate. Generally the QC materials are run and analyzed independent of the Automation System. This manual process works OK for a QC regimen that only demands QC on a per shift or per day basis. However, quality control procedures that call for running a calibration or control assay every “n” assays present a significant challenge in a multi-analyzer automated clinical analyzer system. If, for example, four analyzers are each performing ten assays that require a calibration or control assay be conducted every 24 sample assays, the conveyor system linking the analyzers together will become highly concentrated with calibration or control liquids, adversely affecting overall system throughput.